Cooling means for reflecting device

ABSTRACT

This reflecting device is for use wherein the reflecting surface is subjected to heat and includes a thick backing member with channels on one surface thereof with one surface of a cover member fixed to said channeled surface forming passages. A reflecting surface is formed on the other surface of the cover member and a manifold system directs a coolant through the passages formed by the channels of the backing member and the mating surface of the cover member. The manifold system includes an inlet and an outlet which can be connected to any desired control means to achieve the proper flow. This cooling arrangement not only provides the cooling necessary to maintain the reflecting device in an operating condition but also maintains the high quality of the reflecting surface.

United States Patent McLafferty et a].

[451 Jan. 25, 1972 [541 COOLING MEANS FOR REFLECTING DEVICE 3,488,1101/1970 Evog ..350/3l0 FOREIGN PATENTS OR APPUCATIONS PrimaryExaminerDavid Schonberg Assistant Examiner-Michael J Tokar Attorney-JackN. McCarthy [5 7] ABSTRACT This reflecting device is for use wherein thereflecting surface is subjected to heat and includes a thick backingmember with channels on one surface thereof with one surface of a covermember fixed to said channeled surface forming passages. A reflectingsurface is formed on the other surface of the cover member and amanifold system directs a coolant through the passages formed by thechannels of the backing member and the mating surface of the covermember. The manifold system includes an inlet and an outlet which can beconn cted to any desired control means to achieve the proper flow. fihiscooling arrangement not only provides the cooling necess ry to maintainthe reflecting device in an operating condition but also maintains thehigh quality of the reflecting surfaces? 10 Claims, 4 Drawing Figures lPATENTEU JAN 2 5 I972 SHEET 1 fiF 2 )7 M if CROSS-REFERENCE TO RELATEDAPPLICATIONS Application Ser. No. 34,672, filed May 5, 1970, which is acontinuation of application Ser. No. 804,386, filed Mar. 3, 1969 forCooling Means for Reflecting Device, contains subject matter which is animprovement to the subject matter herein.

BACKGROUND OF THE INVENTION Reflecting surfaces have been made by havingpassages drilled radially into a block adjacent the reflecting surface;however, this method was not satisfactory due to difficulty inmanifolding the passages and having the passages follow a curvedsurface. The passages also would have to be large and the materialthickness from the surface of the cooling channel would be excessive.

SUMMARY OF THE INVENTION This reflecting device permits closedimensional tolerance passages and simplified manifolding. The coolantpassages can also be formed of complex contours with the same tolerance.This construction also gives flexibility of materials in that therequirement for thermal stability of the material can be relaxed infavor of other requirements if necessary. The method of making areflecting device such as this is greatly simplified and the qualitygreatly increased. Quality means that the reflecting surface ismaintained to produce diffraction limited optics.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a top view showing thelocation of the inlet and outlet along with the manifolds and thecooling passages.

FIG. 2 is a view taken along the line 2-2 of FIG. 1.

FIG. 3 is a view taken along the line 33 of FIG. 1.

FIG. 4 is an enlarged view of a portion of FIG. 3 showing the coolingpassages in detail.

DESCRIPTION OF THE PREFERRED EMBODIMENT The reflecting device shownincludes a backing member 2 and a platelike cover member 4. Whilemembers 2 and 4 are shown as substantially circular in shape (see FIG.1), other contours desired can be used, such as rectangular. The backingmember 2 is shown as being constructed from two parts, 6 and 8.

Part 6 is relatively thick and has arcuate slots 10 and 12 cut into oneend surface 14. These slots, 10 and 12, extend inwardly to an innersurface 16 adjacent the other end surface 18 of part 6, and are formedhaving the same radial distance from the center of the part 6 of thecircular backing member 2. Each slot, 10 and 12, is adjacent the outeredge of the part 6 and extends substantially through an arc of 180.

A passage 20 extends in a radial direction within part 6 and connectsthe midpoint of the arcuate slot 10 with the exterior of the backingmember 2. A passage 22 extends in a radial direction within part 6 andconnects the midpoint of the arcuate slot 12 with the exterior of thebacking member 2. These passages 20 and 22 are positioned atdiametrically opposed locations.

Channels, or grooves, 24 are formed in the surface 18 of part 6. Thissurface 18 is shaped to receive one surface 26 of the platelike covermember 4. The channels 24 are rectangular in cross section with webs 28being formed therebetween.

The channels are positioned in a parallel relationship with one end ofeach channel being connected to the slot 10 at its inner surface 16 andthe other end of each channel being connected to the slot 12 at itsinner surface 16.

Part 8 is a manifold cover having a surface 30 which covers the openends of slots 10 and I2 and forms two manifolds 32 and 34 therewith,respectively. This surface 30 of part 8 is fixed to surface 14 of part 6so as to have a leakproof attachment. Any fixing means can be used whichwill provide this leak iroof attachment, such as brazin Platelr e covermember 4 has its surface 26 fixed to surface 18 of part 6 which includesthe tops of the webs 28. This surface 26 forms a plurality of passages36 with channels 24. These surfaces 18 and 26 are also fixed together soas to have a leakproof attachment. Any fixing means can be used whichwill provide this leakproof attachment, such as brazing. The outersurface 38 of platelike cover member 4 is made into a reflectingsurface.

To align the part 8 and the platelike cover member 4 with part 6 forfixing them together aligning pin means are shown. To position the part8 with part 6 holes 40 and 42 are aligned and pins 44 are pressed intoplace. To position the platelike cover member 4 with part 6 holes 46 and48 are aligned and pins 50 are pressed into place.

In operation, as shown in FIG. 1, a coolant can enter passage 22, flowinto manifold 34 and be directed into one end of all the passages 36.The coolant flows through the passages 36 adjacent the reflectingsurface 38 to the manifold 32 where it exits through passage 20. Anycontrol means desired can be vused to control the flow of coolant liquidthrough the reflecting device which will maintain the flow at a ratewhich will prevent the temperature difference between the reflectingsurface 38 and the surface 18 of part6 from contributing to thermaldistortions.

In a reflecting device, or mirror, constructed in this manner, thethickness of the backing member 2 was made approximately 16 times thethickness of the platelike cover member 4. The material used to form thebacking member 2 and the platelike cover member 4 was copper. Thismaterial was used since it has a high rate of conductivity. While othercoolants can be used, water was used. The reflecting surface formed onsurface 38 can be made in many ways. In the construction referred to,the copper platelike cover member 4 was coated with electroless nickel,which was then coated by vapor deposited gold-chromium, and polished.

We claim:

1. An optical reflecting device for operating under heat comprising athick backing member having a metallic surface of a predetermined shape,a second relatively thin metallic platelike member fixed to the surfacethereof, one of said members having channels on the side facing theother member, said channels forming webs therebetween, the free faces ofthe webs being fixed to the other member, said channels forming passageswith the other member, a coolant manifold system comprising at least twomanifolds, said manifold system being connected to said passages, saidfree face of said second member being treated to form a reflectingsurface.

2. A reflecting device as set forth in claim 1 wherein the manifoldsystem is formed within the device.

3. A reflecting device as set forth in claim 2 wherein said thickbacking member has a manifold formed in each side thereof with saidchannels being connected therebetween.

4. A reflecting device as set forth in claim 1 wherein the contour ofthe channels is rectangular.

5. A reflecting device as set forth in claim 1 wherein means directs acoolant into said manifold system for flow through said passages.

6. A reflecting device as set forth in claim 1 wherein the ratio betweenthe thickness of said backing member and the thickness of the secondmember thickness is large.

7. A reflecting device as set forth in claim 1 wherein the free face ofthe second member has a layer of reflective material thereon.

8. A reflecting device as set forth in claim 1 wherein the channels areformed on the surface of said thick backing member.

9. A reflecting device as set forth in claim 3 wherein the channels areformed on the surface of said thick backing member, each end of saidchannels intersecting one of said manifolds.

10. A reflecting device as set forth in claim I wherein the free facesof the webs are brazed to the other member.

1. An optical reflecting device for operating under heat comprising athick backing member having a metallic surface of a predetermined shape,a second relatively thin metallic platelike member fixed to the surfacethereof, one of said members having channels on the side facing theother member, said channels forming webs therebetween, the free faces ofthe webs being fixed to the other member, said channels forming passageswith the other member, a coolant manifold system comprising at least twomanifolds, said manifold system being connected to said passages, saidfree face of said second member being treated to form a reflectingsurface.
 2. A reflecting device as set forth in claim 1 wherein themanifold system is formed within the device.
 3. A reflecting device asset forth in claim 2 wherein said thick backing member has a manifoldformed iN each side thereof with said channels being connectedtherebetween.
 4. A reflecting device as set forth in claim 1 wherein thecontour of the channels is rectangular.
 5. A reflecting device as setforth in claim 1 wherein means directs a coolant into said manifoldsystem for flow through said passages.
 6. A reflecting device as setforth in claim 1 wherein the ratio between the thickness of said backingmember and the thickness of the second member thickness is large.
 7. Areflecting device as set forth in claim 1 wherein the free face of thesecond member has a layer of reflective material thereon.
 8. Areflecting device as set forth in claim 1 wherein the channels areformed on the surface of said thick backing member.
 9. A reflectingdevice as set forth in claim 3 wherein the channels are formed on thesurface of said thick backing member, each end of said channelsintersecting one of said manifolds.
 10. A reflecting device as set forthin claim 1 wherein the free faces of the webs are brazed to the othermember.